JP2009058879A - Liquid crystal display and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display capable of reducing a rubbing defect region generated during rubbing process, and its manufacturing method. <P>SOLUTION: In the liquid crystal display 1 in which pixels PX are delta arranged, an array substrate 3 comprises a plurality of scanning lines Y; a plurality of signal lines X which are crossing the scanning lines Y; a plurality of thin film transistors 13 arranged around the vicinity of the cross point of the scanning lines Y and the signal lines X corresponding to respective pixels PX; a plurality of pixel electrodes 9 connected with respective thin film transistors 13; and an orientation film 33 which is formed while covering the plurality of pixel electrodes 9 and subjected to the rubbing process. The plurality of signal lines X are extending toward column direction while meandering along the delta arranged pixels PX, wherein the corner parts 10 of the signal lines X are cut off, and the inclination parts 10a are formed in the rubbing direction D of the rubbing cloth in the rubbing process. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device in which pixels in a delta arrangement are formed on an array substrate and a manufacturing method thereof.

  In recent years, active matrix liquid crystal display devices in which switching elements for setting the potential of each pixel electrode are arranged near the intersection of scanning lines and signal lines have been put into practical use, and a high-contrast image can be obtained with little afterimage. The liquid crystal display device is widely used because of its high reaction speed. In such a liquid crystal display device, it is known that pixels constituting a display region are delta-arranged as a means for realizing excellent color reproducibility with little viewing angle dependency and realizing smooth video display (for example, Patent Document 1).

  However, when the pixels are arranged in a delta arrangement, the signal lines are formed in a zigzag shape along the pixels, and the surface of the alignment film to be rubbed has an uneven shape corresponding to the signal lines. In response, a rubbing failure area is likely to occur during the rubbing process. In this rubbing failure region, the alignment state of the liquid crystal molecules becomes non-uniform, resulting in a decrease in contrast and display unevenness, thereby impairing optical characteristics and causing a decrease in yield.

In particular, liquid crystal display devices used for portable products such as DSC (Digital Still Camera) and DCV (Digital Video Camera) are highly demanded for miniaturization and weight reduction. Although the elements are formed at a high integration rate, in such a case, the problem caused by the rubbing failure area becomes more remarkable.
JP-A-2005-121954

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal display device that can reduce a rubbing failure region that occurs during rubbing treatment, and a method for manufacturing the same.

  The liquid crystal display device of the present invention is a liquid crystal display device comprising an array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate, wherein the array substrate displays an image. A plurality of pixels are delta-arranged in the region, and are arranged corresponding to each pixel in the vicinity of a plurality of scanning lines, a plurality of signal lines intersecting with the scanning lines, and an intersection position of the scanning lines and the signal lines. A plurality of thin film transistors, a plurality of pixel electrodes connected to each of the thin film transistors, and an alignment film formed so as to cover the plurality of pixel electrodes and subjected to a rubbing process, and the plurality of signal lines include: The signals meander along the pixels arranged in the delta arrangement and extend in the column direction, and an inclined portion is formed along the rubbing direction in the rubbing process at the corner of the meandering portion of the signal line. And wherein the are.

  According to another aspect of the present invention, there is provided a liquid crystal display device comprising an array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate, wherein the array substrate displays an image. A plurality of pixels are delta-arranged in the display region, a plurality of scanning lines, a plurality of signal lines intersecting the scanning lines, an interlayer insulating film that insulates the scanning lines and the signal lines, and the scanning lines And a plurality of thin film transistors arranged corresponding to each pixel in the vicinity of the intersection of the signal lines, a resin film formed to cover the signal lines, and a plurality of pixel electrodes connected to the thin film transistors The plurality of signal lines meander along the delta-arranged pixels and extend in the column direction, and a step-adjusting insulating film is adjacent to the side of the signal line on the interlayer insulating film. Formation It is characterized in that is.

  Furthermore, the manufacturing method of the liquid crystal display device of the present invention includes an array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate, and a plurality of pixels in a display region for displaying an image. Are formed in a delta arrangement, and a plurality of scanning lines on the array substrate and a plurality of signal lines extending in the column direction by meandering along the delta arrangement pixels intersecting the scanning lines are formed. Forming a plurality of thin film transistors arranged corresponding to each pixel in the vicinity of the intersection of the line and the signal line, and a plurality of pixel electrodes connected to each thin film transistor, and covering the plurality of pixel electrodes with an alignment film In the method for manufacturing a liquid crystal display device thus formed, the plurality of signal lines are formed with inclined portions having a predetermined angle at the corner portions of the meandering portion, and the arrangement is performed along the inclined portions. Characterized in that rubbed the film.

  Furthermore, the method for manufacturing a liquid crystal display device of the present invention includes an array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate, and a plurality of display areas in the display region for displaying an image. A plurality of scanning lines on the array substrate and a plurality of signal lines extending in the column direction by meandering along the delta-arranged pixels crossing the scanning lines on the array substrate; A plurality of thin film transistors arranged corresponding to each pixel in the vicinity of the intersection of the scanning line and the signal line, and a plurality of pixel electrodes arranged via a resin film covering the signal line and connected to the thin film transistor In the method for manufacturing a liquid crystal display device, after forming the step adjustment insulating film adjacent to the side of the signal line, the signal line and the step adjustment insulating film are formed on the resin layer. Characterized by coating.

  As described above, according to the present invention, a defective rubbing region that occurs during the rubbing process is reduced, and a high-quality liquid crystal display device with few image quality defects such as a decrease in contrast and display unevenness and a method for manufacturing the same are obtained. Can do.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a circuit diagram schematically illustrating a configuration of a liquid crystal display device 1 according to an embodiment of the present invention, and FIG. 2 is a diagram schematically illustrating a planar structure of pixels arranged in a delta arrangement in the liquid crystal display device 1. 3 is a cross-sectional view taken along the line AB of FIG. 2 showing the configuration of the switching element and the auxiliary capacitor in the liquid crystal display device 1, and FIG. 4 shows the signal lines X and the scanning lines Y in the liquid crystal display device 1. It is CC sectional view taken on the line of FIG. 2 which shows a structure.

  As shown in FIGS. 1 to 3, the liquid crystal display device 1 includes an array substrate 3 and a counter substrate 5 formed using insulating transparent substrates 4 and 6 such as glass, and between the substrates 3 and 5. The array substrate 3 is provided with a plurality of pixels PX arranged in a delta arrangement in a display area DSP for displaying an image.

  These pixels PX consist of three types of red pixels PXR, green pixels PXG, and blue pixels PXB, and form a linear pixel column along the row direction of the array substrate 3 and along the column direction. A zigzag delta-arranged pixel row shifted by ½ pitch is formed.

  The array substrate 3 is formed with a plurality of pixel electrodes 9 corresponding to the respective pixels PX in the display area DSP, and the counter substrate 5 is opposed to all the pixel electrodes 9 arranged in a delta arrangement. A single counter electrode 11 is provided. PL1 and PL2 are polarizing plates attached to the array substrate 3 and the counter substrate 5.

  As shown in FIG. 1, the array substrate 3 includes m × n pixel electrodes 9, n scanning lines Y (Y1 to Yn), m signal lines X (X1 to Xm), The scanning line driving circuit 50 includes m × n switching elements 13 and n auxiliary capacitance lines AY, and sequentially supplies scanning signals to the n scanning lines Y in the peripheral area of the display area DSP. A signal line driving circuit 52 for supplying a video signal to the main signal line X and a controller 54 for controlling the driving circuits 50 and 52 are provided, and the pixel electrodes 9 in each row are supplied via the switching elements 13. Each pixel potential is set according to the signal.

  The scanning lines Y are made of Al, Mo, W alone or an alloy having a thickness of about 0.3 μm, and are formed linearly along the rows of the pixel electrodes 9. The signal line X is made of Al, Mo, W alone or an alloy having a thickness of about 0.7 μm, and is formed by meandering in a zigzag manner along a row of pixel electrodes 9 arranged in a delta arrangement. An inclined portion 10 a is formed at the corner portion 10.

  More specifically, as shown in FIG. 2, the signal line X is a direction (rubbing direction) in which the corner portion 10 of the signal line X rubs a rubbing cloth during a rubbing process for forming an alignment film 33 described later. It is excised along D and forms an inclined portion 10a along the direction D. The inclined portion 10a is set at an angle of 45 °, for example.

  As shown in FIG. 3, the switching element 13 is an n-channel type thin film transistor having a semiconductor layer 15 formed of a polysilicon film, and is arranged in the vicinity of the intersection of the corresponding scanning line Y and the corresponding signal line X. Are associated with each pixel electrode 9. The semiconductor layer 15 is disposed on an undercoating layer disposed on the glass substrate 4, and has a drain region 15D and a source region 15S formed by doping impurities on both sides of the channel region 15C.

  The switching element 13 includes a gate electrode 17, a drain electrode 19, and a source electrode 21.

  The gate electrode 17 is formed integrally with the scanning line Y, is disposed to face the semiconductor layer 15 via the gate insulating film 23, and is covered with the interlayer insulating film 25.

  The drain electrode 19 and the source electrode 21 are electrodes electrically connected to the drain region 15D and the source region 15S of the semiconductor layer 15, and the drain electrode 19 is a signal line X formed on the interlayer insulating film 25. A part of the source electrode 21 is connected to the upper source electrode 22 formed on the interlayer insulating film 25.

  On the interlayer insulating film 25, a step adjusting insulating film 40 is formed adjacent to the side of the signal line X, as shown in FIG. The step-adjusting insulating film 40 is formed thinner than the signal line X. For example, the step-adjusting insulating film 40 is made of an insulating film having a thickness of about 0.6 μm, and is interposed between the interlayer insulating film 25 and the signal line X formed thereon. The steep steps that occur are alleviated.

  The upper source electrode 22 is electrically connected to the pixel electrode 9 through a contact hole formed in the insulating resin layer 29 that covers the interlayer insulating film 25, the signal line X, the step adjustment insulating film 40, and the upper source electrode 22. Thus, the switching element 13 is connected to the scanning line Y and the signal line X, is made conductive by the driving voltage from the scanning line Y, and applies the signal voltage from the signal line X to the pixel electrode 9.

  The auxiliary capacitance line AY is made of Al, Mo, W alone or an alloy having a thickness of about 0.3 μm, and is capacitively coupled to the auxiliary capacitance electrode 31 to form the auxiliary capacitance CS, and is substantially the same as the scanning line Y. They are formed in parallel. Specifically, the auxiliary capacitance electrode 31 is formed of an impurity-doped polysilicon film and is disposed on the undercoating layer that is the same layer as the semiconductor layer 15. Further, the auxiliary capacitance electrode 31 is electrically connected to the upper source electrode 22 through a contact hole that penetrates the gate insulating film 23 and the interlayer insulating film 25, whereby the source electrode 21 of the switching element 13, the pixel The electrode 9 and the auxiliary capacitance electrode 31 have the same potential. On the other hand, at least a part of the auxiliary capacitance line AY is disposed to face the auxiliary capacitance electrode 31 through the gate insulating film 23 and is set to a predetermined potential. With such a structure, the auxiliary capacitor CS is formed.

  The resin layer 29 is made of a thick light-transmitting resin having a thickness of about 2 μm and includes colored layers 29R, 29G, and 29B that are colored in three primary colors such as red, green, and blue, respectively. The color filter layer is formed.

  The red colored layer 29R, the green colored layer 29G, and the blue colored layer 29B are arranged, for example, as shown in FIGS. 2 and 3, and the pixel electrodes 9 of the red pixel PXR, the green pixel PXG, and the blue pixel PXB, respectively. Assigned.

  A columnar spacer 35 made of a colored resin such as a black resin is formed on the resin layer 29, and an alignment film 33 is formed so as to cover the entire plurality of pixel electrodes 9.

  The alignment film 33 is subjected to a so-called rubbing process in which the surface of the alignment resin film formed of polyimide resin or the like is rubbed in a direction indicated by an arrow D in FIG. A large number of fine scratches are formed so as to extend in the rubbing direction of the rubbing cloth, and the liquid crystal molecules contained in the liquid crystal layer 7 are aligned in the extending direction of the scratches.

  On the other hand, the counter substrate 5 includes a counter electrode 11 formed on the transparent substrate 6 and an alignment film 34 covering the counter electrode 11 in the display area DSP. The counter electrode 11 is formed of a light transmissive conductive member such as ITO. The alignment film 34 aligns liquid crystal molecules contained in the liquid crystal layer 7 in a predetermined direction with respect to the counter substrate 5.

  When the array substrate 3 and the counter substrate 5 as described above are arranged so that the alignment films 33 and 34 face each other, the columnar spacer 35 forms a predetermined gap between the substrates 3 and 5, and this gap A liquid crystal composition is enclosed to constitute the liquid crystal layer 7.

  As described above, according to the present invention, the corner portion 10 of the signal line X is not cut off because the corner portion 10 of the signal line X is cut off and the inclined portion 10a is formed along the direction D in which the rubbing cloth is rubbed. Compared to the case, it is possible to suppress the rubbing failure that occurs in the corner portion 10 of the signal line X.

  Further, in each element constituting the pixel PX such as the signal line X, the scanning line Y, and the switching element 13, the signal line X is thicker than the other constituent elements, so that the rubbing process is performed on the surface of the alignment resin film. Has a high step due to the signal line X, and in particular, the bulge generated in the alignment resin film is higher at the intersection position P between the signal line X and the auxiliary capacitance line AY, and rubbing failure tends to occur at these positions. In the present invention, the step adjusting insulating film 40 is disposed along the signal line X, and the steep step is relaxed to be a gentle step. Therefore, the rubbing cloth surface follows when rubbing with the rubbing cloth. Easy rubbing failure.

  Further, by combining this configuration with the configuration provided with the above-described inclined portion 10a, it becomes possible to more effectively suppress the rubbing failure.

  In the above embodiment, the case where the color layers 29R, 29G, and 29B for forming the color filter layer are provided on the array substrate 3 side has been described. However, the color filter layer is configured to be disposed on the counter substrate 5 side. It is also possible to do.

1 is a circuit diagram schematically showing a configuration of a liquid crystal display device according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a planar structure of delta-arranged pixels in the liquid crystal display device of FIG. 1. It is the sectional view on the AB line of FIG. It is CC sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device 3 ... Array substrate 4, 6 ... Transparent substrate 5 ... Opposite substrate 7 ... Liquid crystal layer 9 ... Pixel electrode 10 ... Corner | angular part 10a ... Inclined part 11 ... Counter electrode 13 ... Switching element 23 ... Gate insulating film 25 ... Interlayer insulating film 29 ... Resin film 33, 34 ... Alignment film 40 ... Step adjusting insulating film D ... Rub direction AY ... Auxiliary capacitance line DSP ... Display area PX ... Pixel CS ... Auxiliary capacitance

Claims (6)

In a liquid crystal display device comprising an array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate,
The array substrate has a plurality of pixels arranged in a delta arrangement in a display area for displaying an image, a plurality of scanning lines, a plurality of signal lines intersecting the scanning lines, and intersection positions of the scanning lines and the signal lines A plurality of thin film transistors arranged corresponding to each pixel in the vicinity; a plurality of pixel electrodes connected to each of the thin film transistors; an alignment film formed to cover the plurality of pixel electrodes and subjected to a rubbing process; With
The plurality of signal lines meander along the delta-arranged pixels and extend in the column direction, and an inclined portion along the rubbing direction in the rubbing process is formed at a corner of the meandering portion of the signal line. A liquid crystal display device. In a liquid crystal display device comprising an array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate,
The array substrate includes a plurality of pixels arranged in a delta arrangement in a display area for displaying an image, and insulates the plurality of scanning lines, the plurality of signal lines intersecting the scanning lines, and the scanning lines and the signal lines. An interlayer insulating film, a plurality of thin film transistors arranged corresponding to each pixel in the vicinity of the intersection of the scanning line and the signal line, a resin film formed to cover the signal line, and connected to each thin film transistor A plurality of pixel electrodes,
The plurality of signal lines meander along the delta-arranged pixels and extend in the column direction, and a step-adjusting insulating film is formed on the interlayer insulating film adjacent to the side of the signal line. A liquid crystal display device. The array substrate includes a plurality of auxiliary capacitance lines substantially parallel to the scanning lines,
The liquid crystal display device according to claim 2, wherein the step-adjusting insulating film is formed at a position intersecting with the storage capacitor line. The array substrate includes an alignment film formed so as to cover the plurality of pixel electrodes and subjected to a rubbing process,
4. The liquid crystal display device according to claim 2, wherein an inclined portion is formed along a rubbing direction in the rubbing process at a corner portion of the meandering portion of the signal line. An array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate, wherein a plurality of pixels are delta-arranged in a display area for displaying an image, and on the array substrate A plurality of scanning lines and a plurality of signal lines extending in the column direction meandering along the pixels that intersect with the scanning lines and are delta-arranged are formed, and each pixel is located near the intersection of the scanning lines and the signal lines. In a method of manufacturing a liquid crystal display device, a plurality of thin film transistors arranged correspondingly and a plurality of pixel electrodes connected to each thin film transistor are formed, and an alignment film is formed covering the plurality of pixel electrodes.
An inclined portion having a predetermined angle is formed at a corner portion of the meandering portion in the plurality of signal lines, and the alignment film is subjected to rubbing treatment along the inclined portion. . An array substrate, a counter substrate, and a liquid crystal layer held between the array substrate and the counter substrate, wherein a plurality of pixels are delta-arranged in a display area for displaying an image, and on the array substrate A plurality of scanning lines and a plurality of signal lines extending in the column direction meandering along the pixels that intersect with the scanning lines and are delta-arranged are formed, and each pixel is located near the intersection of the scanning lines and the signal lines. In a manufacturing method of a liquid crystal display device in which a plurality of thin film transistors arranged correspondingly and a plurality of pixel electrodes arranged via resin films covering the signal lines and connected to the thin film transistors are formed,
A method of manufacturing a liquid crystal display device, comprising: forming a step-adjusting insulating film adjacent to a side of the signal line; and covering the signal line and the step-adjusting insulating film with the resin layer.

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